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A338151
a(n) = (n+1)^A338136(n) mod n^A338150(n).
3
9, 4, 9, 16, 25, 169, 25, 64, 81, 100, 25, 27, 729, 121, 49, 256, 289, 324, 81, 64, 243, 484, 49, 576, 5929, 676, 169, 784, 121, 125, 225, 100, 1089, 841, 7921, 1000, 343, 196, 81, 1600, 169, 216, 441, 361, 2025, 2116, 289, 2304, 2401, 256, 625, 2704, 2809, 441
OFFSET
2,1
COMMENTS
a(n) is a perfect power, and a(n) == 1 + n*A338136(n) (mod n^2).
LINKS
FORMULA
a(n) = (n+1)^A338136(n) mod n^A338150(n).
EXAMPLE
a(2) = 3^A338136(2) mod 2^A338150(2) = 3^6 mod 2^4 = 3^2 = 9.
a(13) = 14^A338136(13) mod 13^A338150(13) = 14^2 mod 13^2 = 3^3 = 27.
MAPLE
g:= proc(n) local k, x, j, F;
for k from 2 to n-2 do
x:= (n+1)^k;
for j from 2 to floor(k*log[n](n+1)) do
F:= ifactors(x mod (n^j))[2];
if igcd(op(map(t -> t[2], F))) > 1 then return x mod (n^j) fi
od od
end proc:
g(2):= 9: g(3):= 4:
map(g, [$2..40]);
CROSSREFS
Sequence in context: A355563 A332500 A253203 * A255642 A088701 A153698
KEYWORD
nonn
AUTHOR
J. M. Bergot and Robert Israel, Oct 12 2020
STATUS
approved